Signaling-key.



No. 855,168. PATENTED MAY 28, 1907.

0. 1?. FORSBERG & J. A. BIRSFIELD.

SIGNALING KEY.

APPLICATION FILED OOT. 27,1902.

6 SHEETS-SHEET 1.

MAZQQLQQQ No. 855,168. I PAl'lllST'lED MAY 28, 1907.

O. P. FORSBERG & J. A. BIRSPIELD.

SIGNALING KEY.

APPLICATION FILED 00121.1902.

6 SHEETS-SHEET 2.

Ogcar 6 f'graberg ril il PATENTED MAY 28, 1907.;

0. F. PORSBERG & J. A. BIRSFIELD. SIGNALING KEY. APPLICATION FILED00127.19.

6 SHEETS-SHEET s lm mnumunm 6 MW Wlfnes hire/Wars: .Qgcar f [maskerg 721M I QM No. 855,168. A PATENTED MAY 28, 1907.

0. P. FORSBERG & J. A. BIRSFIELD.

SIGNALING KEY.

APPLIUATION FILED OUT. 27. 1902.

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No. 855,168. PATENTED MAY 28, 1907. 0. F. FORSBBRG & J. A. BIRSFIBLD.

SIGNALING KEY. APPLIOA TI 0N rum) 001'. 27,1902.

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No. 855,168. PATENTED MAY 28, 1907. 0. F. FORSBERG & J; A. BIRSPIBLD.

SIGNALING KEY.

APPLICATION FILED 001'. 27, 1902.

a sums-sum e.

Ogagr foraerg I Ja/ga fl/ns fez/a v YW K ALL-Wm UNITED STATES osoiiar.FORSBERG AND PATENT OFFICE.

JULES A. BIRSFIELD, OF CHICAGO, ILLINOIS, AS-

CORPORATION OF ILLINOIS.

SIGNALING-KEY.

' No. sea-ice.

Specification of Letters Patent.

Patented. May 28, 1907.

Application filed October 27,1902. Serial No. 128,871.

To It/IZ whom, it may concern.-

Be it known that we, OSCAR F. FORSBERG and Jonas A. BIRSFIELD, citizensof the United States, residing at Chicago, in the county of cook andState of Illinois, have invented a certain new and useful Im rovement inSignaling-Keys, of which the following is a full, clear, concise, andexact description.

for telephone switchboards.

Our invention relates to a signaling key Where a number of substationtelephone instruments are connected on a single circuit or party line itis not uncommon to signal the individual stations from thecentralofiiceswitchboard by sending out current to ring all the bells at once butaccording to a certain understood code-that is to say, a long ring forone station, a sllort ring for another, two short rings for another andso on:

We have devised an improved key which when-initially set .by theoperator will thereafter act automatically and accurately to ,mittermembers are transmit any desired signal, whether that signal be a merearbitrar number of rings or a code of long and s iort rings to followone another in a given sequence.

.In the key of our invention a number of transmitter members arearranged so that any one of them may be brought into operative relationto the switch that applies the signaling current, and motor mechanism isprovided which may be set by the attendant to effect the operation ofthe transmitting device, whereby any one of thepredetermined signals maybe sent, dependent upon the particular transmitter member which has beenselected. Preferably, the transtoothed bars disposed longitudinally upona sliding cylinder or drum which is moved longitudinally by means of asuitably-mounted plunger. In the operation of the device the rotation ofthe plunger rotates the cylinder to bring a particular one of thetoothed transmitter bars into operative relation to a contact springwhich controls the application of ringing current. Then when thecylinder has becnde ressed the motor mechanism which is provided with anescapement) slowly returns said cylinder to its normal position, and inits journey the teeth of the particular transmitter-bar selected. arebrought one after another into engagement with the switch spring,causing the latter to move to and fro to make and break the circuit. Thesignal transmitted isthusdependent upon the particular transmittermember brought into play, which was initially determined by rotating theplunger through a given are. The key of our invention will beparticula'iy described and further features thereof explained in detailby reference to the accompanying drawings, in which Figure 1 is a planview of the key as seen by the operator; Fig. 2 is a side elevationthereof, looking from the left hand side; Fig. 3 is a sectionalelevation; Fig. 4 is'a detail sectional view of the travelingtransmitter drum and associated parts; Fig 5 is a view'similar to Fig. 3showing the plunger partially depressed; Fig. 6 is a sectional plan viewon line 6-6 of Fig. 5, sh0wing the gearing for rotating the transmitterdrum; Fig.- 7 is an elevation partly in section of the key as seen fromthe ri ht hand side, showing the plunger fully epressed; Fig. 8 is adetail sectionalview oh line 88 of Fig. 5. Fig. 9 is a view similar toFig. 8 but showing the transmitter drum in an intermediate osition. Fig.10 is a vertical transverse section on line 10-10 I of Fig. 2. Fig. 1-1is a similar view showing the plunger depressed. Fig. 12 isa circuitdiagram illustrating how the key shown in Figs. '111 may be connectedfor use with an. operators cord circuit, to signal any one of tenstations of a party line.

The same letters of reference are used to designate the same partswherever they are shown.

Referring first to the diagram Fig. 12, to illustrate the application ofthe invention, a metallic circuittelephone line 1 2 is indicated,extending from ten substations (five bells on each side of the line) toa spring jack terminal at a central office, where connection may be madewith the line by means of the operators plug and cord circuit. Thetwostrands of the cord circuit are 'connectedred spectively to a pair ofcontact springs a a of 1 co the ringing ke and other springs 15 b,which. are connected with extensionsfif 4 ofthe cord circuit, and arenormally 'held .under tension tomake contact with springs a a resectivel so that the cord circuit may nor.- ma ly bee 'ectricallycontinuous. The plununi tacts c c with the alternate contact anvils a aof springs a a respectively. When plunger a is depressed, a narrowerportion of the insulating piece I) is brought between springs b b sothat these springs move toward one another, breaking contact withsprings a a, respectively. The depression of the plunger also brings theperiphery of the insulating sector-shaped wedge -a. into engagement withone or the other of the springs a a, dependent upon the position ofrotation Y of the plunger; and the spring so engaged is thrust out intocontact with its alternate anvil, which is connected with generator. Theother spring of the pair is allowed to contact with its grounded restinganvil. In short, the depression of the plunger (1 interruptsthe cordcircuit, grounds one side of the circuit and connects the other side tothe calling generator, thus ringing out on one side or the other of theline dependent upon which of the springs a a has been engaged by thewedge piece a. plunger the application of the ringing current iscontrolled by the switch contacts 0 c", and we will now proceed todescribe the mechanism of our invention by which these contacts may'be'opened and closed automatically to send any desired signal.

The key as seen by the operator appears as shown in Fig. 1. The plungerwhich is mounted in bearings so that it may both rotate axially andslide longitudinally, projects throu h the dial plated and is furnishedwith a-knob or button a by which it may be manipulated. It also carriesa .pointer which indicates its angular position upon the dial.

In a suitable framework below the dial plate-that is, below theswitchboard table,

is the mechanism of the key. The lower part of the framework supportsthe main switch springs a a etc. in position to be actuated by theinsulating collar b and sector-shaped wedge piece a which are carried bythe plunger. A compression-spring a encircles the lower portion of theplunger, andbeing confined between the framework or bearing and thelower edge of the collar 1), serves to yieldingly maintain the plungerin an elevated position.

The signal-producing switch springs c c are provided with an actuatingspring or lever 0 the end whereof is positioned to :be engaged by thetransmitter members f,

which are shown'as toothed bars carried upon During the depression ofthe a cylinder g. Said cylinder is mounted to slide longitudinally upona vertical shaft g, and also rotates with said shaft. The toothedtransmitter bars are disposed longitudinally on the sides of thecylinder, so that by rotating the cylinder any one of said transmitterbars may be brought into operative relation to the actuating spring 0 ofthe si naling switch. Thenas the cylinder is slid along the shaft g, theteeth of the selected transmitter bar one after the other engage theprojecting end of the spring 0 whereby the spring 0 is caused to makeand break contact with its anvil c. A long tooth of course, causes thecontact to be maintained for a little time, while said. toothis-passing, while a short tooth causes only a momentary contact. Anydesired code signal of long and short rings may thus be produced by atransmitter bar having corresponding teeth.

Figs. 5 and 6 show the gearing g which connects the plunger (1. with theshaft g, so that the two rotate together, the indicator d carried by theplunger thus showing the angular position of the cylinder-that is,showing which transmitter bar is in operative relation to thecontrolling switch.

A spring-actuated click lever h, shown most clearly in Fig. 6-, has atooth which engages the teeth of the gear wheel upon the plunger shaft,so that as the plunger is rotated it will move a full step at a time andcome to rest naturally in the properposition to bring the appropriatetransmitter bar fullyin line with the sprin c which it is to actuate. Toprevent the p un er from being rotated while depressed a dog is carriedby a rocking lever k which normally tends to thrust said dog into thepath of the click lever. The sliding cylinder g is mounted to travelwith a sliding carriage m, and when said carriage is at the upper end ofits journey a portion thereof engages a pin carried by the rocking lever7c and moves said lever to withdraw the dog 76 from the path of theclick lever and leave the latter free to vibrate.

The carriage m of the transmitter cylinder is arranged to be depressedby thedepression of the plunger and then slowly returned to its normalposition by mechanism which we shall now proceed to describe.

The transmitter carriage is mounted to slide up and down on a verticalrod Z, and carries a rack bar m which is engaged by a pinion m fixedupon a shaft n. A coiled spring a acting upon said shaft n yieldinglymaintains the carriage m at the upper end of its journey, the springbeing wound up when the shaft n is rotated in a direction to depress thecarriage. The rotation of the shaft n is brought about by means of apinion 0 carried thereon and meshing with a rack 0 carried by theplunger 0. In order that the transmitter carriage may be returnedindependent of the plunger, the latter being held ICC IO ranged torotate therewith As th on the main ance of the escapement,

s ance 5 to the shaft through the agency of a pawl p and cam plate p.The awl is pivoted to a disk n fixed upon the s iaft n, and the camplate p, which is in effect a ratchet wheel of one tooth, is fixed tothe pinion o and arloosely upon the shaft. The rack o carried by theplunger is adapted to engage the pinion whatever the angular position ofsaid plunger, and may be formed as shown of a series of teeth each one I5 of which extends clear around theplungerf the teeth thus forming aseries of beads or annular enlargements upon the plunger.

As the plunger is depressed the rack 0 rotates pinion 0 and cam plate1); this latter 20 engages pawl 12 mounted on the disk n which is fixedupon the shaft n, so that said shaft is rotated, winding up the coiledspring and acting through pinion m and rack bar m to depress thetransmitter carriage m. e plunger reaches the bottom' of its journey,the disk it reaches a positionof rotation such that the pawl p isengaged by a pin p projecting into its path, and'is raised from thenotch of the cam plate 19 whereby 0 the shaft n is released and renderedindependent of the plunger, so that though the plunger remains depressedthe transmitter carriage is returned to its normal position. To retardthis upward movement of the 35 transmitter carriage an escapement isprovided, consisting of a clock train which is connected by means of apawl and ratchet wheel 1' with the shaft '22. When the shaft is rotatedin depressing the plunger the pawl g wheel of the clock train slidesover the teeth of the ratchet wheel without moving the clock train, butthe opposite rotation of the shaft in elevating the transmitter carriageis effected against the resistthe teeth of the ratchet wheelrengagingthe pawl of theclock train to move the same, A detent lever S- engages ashoulder on the plunger (1 and holds said plunger depressed until thetransnutter carriage has been returned to its normal position, Towardthe end of the u ward travel, as the disk 'n approaches t e limit of itsbackward rotation, a cam 8' carried thereby engages the detent lever andmoves the same out to release the plunger,

whereupon the latter is returned quickly to its normal elevated positionby the spring a.

To review briefly the operation, the rotationof the plunger 0rotates'the cylinder 9,

whereby any desired one of the transmitter bars f may be brought intooperative relation to the switch-operating spring finger 0 theparticular bar selected being indicated by the position of the pointeron the dial (1. Then a 5 depression of the plunger depresses the cylsetin operation by I control'of the switch 0 c;

inderg and as the lower endfofits journey is reached the main switchsprings a aft? 1) are actuated, so that the application of ringingcurrent to the circuit is brought under the atthe'same time the shaftnis released and begins to be rotated by the spring to return thetransmitter carriage to its normal position, the movement belng retardedby the clock train.

During the upward travel of the cylinder 7 carriage, the previouslyselected transmitten bar actuates the contact springs c c, and thuscauses the sending of a signal, the character of said signal beingdependent upon the teeth of the transmitter bar in uestion. The plungeris held down and locke against rotation during the transmission of thesignal, but finally is released and returned to its normal position.

Iaving now describedthe preferred embodiment of our invention we claimas new, and desire to secure by Letters Patent the following: I i l. Inaringing key for telephone switchboards, the combination with a switchadapted to control the application of ringing current, of a number oftransmitter members for determining the actuation of said switch,selecting mechanism whereby any one of said transmitter membersintooperative relation to the switch, and motor mechanism arranged tooperate the switch through the agency of the selected transmitter.

2. In a key, the combination with aswitch, of a number of distinctivesignal transmitters, a plunger adapted in its rotation to bring any ofsaid transmitters and the switch into operative correlation, saidplunger being adapted in a longitudinal movement to cause thecooperation of the selected transmitter wilth the switch to produce adistinctive signa 3. The combination with a signal switch, of atransmitter cylinder independent of the circuit of said switch, and aseries of transmitter members carried by said cylinder and arranged tobe selected or brou it into operative relation to the si nal swit tiverotation of the cy incler, the transmitter so selected bein caused toengage and operate the signal switc by the relative longitudinalmovement of the cylinder.

4. In a key, the combination with a rotatable and 1011itudinally-movable plunger, of a main switc operated by the de ressionof the plunger, asubsidiary switc adapted when operated toproducesignalsin the cirmay be brought by the rela- I cuit governed bysaid mainswitch, a number of transmitter members for determining the switch, anyone of said transmitter members being brought into operative relation tothe switch by the rotation of theplunger, a motor mechanism thedepression of the plunger, switch and the selected transmitter memberinto active co-operation in the transmission of a signal and mechanismfor retaining the plunger during the operation of the transmittingmechanism. a

-.5. In a ringing key the combination with a switch for controlling theapplication of ringing current, of a serles of transmitter members, saidmembers being adapted to be se-- lected or brought into operativerelation to the switch, a longitudinally movable plunger,

motor mechanism set in the depression of the plunger adapted to effect amovement of the selected transmitter member to operate said switch, andmeans actuated by the plunger at the end of its downward movementadapted to, release said motor mechanism.

- 6. In a ringing key, the combination with a transmittertor controllingthe application of ringing current, said transmitter comprisrelativemovement ing a switch and a transmitter member adapted to enga e theswitch to determine its operation, 0 a longitudinally-movable plungeradapted in its depression to effect a of the switch and trans mittermemher, motor mechanism set in the depression of the plunger, meansactuated by the plunger at the end of its downward movement to releasethe motor mechanism to effeet a reverse relative movement of the switchand transmitter member, and mech-- vanism also actuated by the plungerat the end of its downward movement operating to establish an operativecondition of the transmitter only during the reverse relative movementof the switch and transmittermember.

7. In a ringing key, the combination with.

' in the depression of the plunger for effecting a reverselongitudinalmovement of the cylinder indepen ent of the plunger, meansactuated by the plunger at the end of'its down-.

ward movement to release said motor mechanism, a catch for holding theplunger depressed during the reverse movement of the c linder, and amain switch actuated while t e plun er is depressed, to establishconnectlon between the aforesaid subsidiary switch and the line.

8. In a ringing key, the combination with v a main switch forcontrolling the application of ringing current to a line, of a plungeradapted to bring the subsidiary .being made holding the adapted whendepressed to operate said switch, a transmitter adapted to determine thecharacter of the-ringing current applied through the main switch, saidtransmitter operative by the depression of the plun' er, a detent levers for holding the plunger epressed and a cam s moved against the detentlever in the operation of the transmitter to release the plunger.

9. In a ringing key, the combination with a switch 0 of a transmittermember f adapted to be moved to actuate saidswitch, a transmittercarriage m, a manually operated plunger for moving said transmittercarriage,

clockwork for returning said carriage to its mechanism for transmittingmotion from the lunger to the transmitter carriage as the p unger isdepressed, means operated at theend of the downward-movement of theplunger to release the transmitter carriage from. the plunger, wherebnormal position,

the oarria e is allowed to return indepen e plunger, a detent lever sfor plunger depressed while the transmitter carriage is returning, and acam s actuated by the clockwork to release the plunger at the end of thereturn movement ofthe transmitter carriage, substantially as descrided.

10. In aringing key,

the combination with a plunger, of a cam plate at rotated by thedepression of the plunger, a disk n and mechanism for coupling the camdisk While the plunger is being depressed, a

device 10 operating to disconnect the disk from the cam plate when theplunger reaches the limit of its downwardmovement, clockwork for causinga reverse rotation of shea e-' disk to return it to its normal osition,tent lever 8 operating to hold t e plunger depressed, a cam s carried bythe disk n and adapted to be brought into engagement with detent lever sto effect the re ease of the plunger as the disk completes its reversemovement, a transmitter membermoved in the rotation f the disk, and aringing switch.

operated by said transmitter member,substantially as described.

plate with the.

roo

- 11. In a ringing key the combination with I a switch for controllingthe a plication of ringing current, of a series 0' transmitter members,a support. therefor, said members being adapted to be selected'orbrought into operative relation tothe switch, a longitudinally-movableplunger, motor mechanism set in the depression of the plunger adapted toefiect a movement of said transmitter support, the selected transmittermember as t e support is moved operating said switch, and means actuatedby the plunger at the end of its downward movement adapted to releasesaid motor mechanism.

Y 12. The combination with a signal switch, eta cylinder, aseries oftransmitter members carried thereby, and -a rotatable plunger adaptedone aly gitu

to rotate said cylinder and bring of said transmitter members, indimeritof the'cylinder an transmitter boards, the ed to control th rent, of

. for actua member to ringing key f combination longitudinal moved causethe selected operate said switch. or telephone switchwith a switchadapt- 6 application of ringing cur a number of transmitter members tingsaid switch; a plunger adapted ated to bring a ny individual trans ed tooperate the I of the selected transmitter;

mitter member'into operative relation to the switch, and motor mechanismset by said 1 5 plunger-in its longitudinal moyement, adaptswitchthrough the agency In Witness whereof, we hereunto subscribe our namesthis 29th ,day of August A. D., 20

OSCAR F1 FoRsBER'G.

JULES A. BIRSFIELD. Witnesses DUNCAN E. WlLLETT, ED IN H. .SMYTHE. I

